Figs. 17 and 18 are a top and sectional view of my improved cap-primer, which differs in some important particulars from the English and other cap-primers now in use. I make a spiral groove, _a a a_, in a plate of brass or other metal, which groove is of such depth and width as to receive the percussion-caps, and to allow them to move freely therein. _b b b_ are caps within said groove. In the center of the primer, under the plate _c c_, is a spiral spring, _d d_, operating like the mainspring of a watch upon its barrels and turning the plate _c c_. This plate has a groove across it which carries a sliding arm, _e e′_, having under its end _e′_ a projecting piece which enters the groove, draws the arm out, and presses upon the row of caps. At the mouth of the spiral groove, where the the cap _b′_ is seen, a steel spring, _f_, checks the cap and counteracts the pressure of the spiral spring _d d_; but when the cap _b′_ is placed upon the tube or nipple the spring _f_ will recede by the withdrawal of the cap, and a new one will be made to occupy its place, and so on until the whole are exhausted. The cover _g_, which in Fig. 17 is shown as raised, is held down by a spring-catch at _h_. There is a spring-catch at _i_, which holds the sliding arm _e_ at its end _e′_, when it is brought round to the inner end of the spiral groove, its use being to detain the arm while the groove is being filled with caps, when it is to be raised, and the arm left at liberty to operate. The spring _d d_ may be wound up by a small key, _k_, or by inserting a screw driver in a notch made for that purpose, or simply by forcing the arm _e e_ round until it is caught by the catch _i_. Fig. 19 is a representation of my ammunition-flask, by means of which all the chambers in my receiver may be simultaneously charged with powder and with balls. It consists of two separate chambers, one of which is a powder and the other a bullet magazine, _a_ being the former and _b_ the latter, the two being connected together by a bayonet-joint at _c_. _d d d_ are charging-tubes adapted in number and position to the mouths of the chambers of the receiver which they are to enter.